CHEM AND BIO HELP AND TIPS HERE

[Fastal]

still dont understand

[nid404]

I'll have to look for my chem guide...I gave my igs last year...so ill really have to look for the books...

[Baladya]

its not a salt..its a carbonate !!!!!!!  so when u put in in acid...effervescent ..bubles of a collurless gas and solid decrease in size

OMG LOL srry i got confused    

[Baladya]

i understand the first 1

but the cathode...? where does the 2h2o come from?

I'm not sure, but i think it might be that when u add oxygen and hydrogen they react. This ofc only if the cathode and anode aren't seperated (like a wall between them)

[Vin]

still dont understand

At negative

Hydrogen loses electrons to the OH^- ions .. its oxidised

2H₂ (g)   +   4OH^- ----->  4 H₂O (l)  +  4 e^-  

At positive

The electrons are accepted by oxygen molecules

Oxygen is reduced to OH^- ions

O2 (g)  +  2H2O  +  4e^-   ---->  4OH^-  

Adding two half equations :

2H2 (g)  +  O  --->  2H2O (l)

i think thts wat  nid  has explained before..

[J.Darren]

I'm not sure, but i think it might be that when u add oxygen and hydrogen they react. This ofc only if the cathode and anode aren't seperated (like a wall between them)

Cathode and Anode are separated by a penetrable membrane which enables Hydrogen and Oxygen to interact.

[CatAly$t]

can somebody explain to me what is continuous and discontinuous variation??

i'm confused 

[DEGO]

1) nitrogen in air to nitrates: @artificial by haber
                                        B natural by lightening
                                        C biological by nodular bacteria and free living nitrogen fixing bacteria
2)fate of nitrates in the soil: @absorbed by the plant
                                        B leached to rivers or lakes
                                        C changed back to nitrogen in air by denitrifying bacteria
3)if it is absorbed plant eaten by animals then either plants or animal die so nitrogenous compound is changed tO AMMONIA in soil
4) the ammonia is changed back to nitrates by effect of nitrifying bacteria thn you go again to (2) to see its fate
i wish this help u understand it and get it   who wanted the nitrogen cycle

[DEGO]

frst the CONTINUOUS VARIATION IS DONE BY THE NATURE: HAVE INTERMEDIATES ,NO SHARP CUT BETWEEN CHAR , NOT CONTROLLED BY GENES (height,weight,.....)
scnd the DISCONTINUOUS VARIATION IS CONTROLLED GENETICALLY: SHARPCUT BETWEEN CHAR ( either boy or girl)(blue or brown eye)....,no inter mediates   
tell me if u got it or not

[Vin]

HAVE INTERMEDIATES ,NO SHARP CUT BETWEEN CHAR

 SHARPCUT BETWEEN CHAR....,no inter mediates   
tell me if u got it or not

mind explaining me this ??

[rhea]

hey any suggestions for the chem practicals?

i suck at pracs 

[nid404]

PAST PAPERS!!

[rhea]

yeah but stuff like relation between concentration and volume...what test to carry out when they randommly ask for testing sumthing...
i dont get theses freaking things AT ALL! :|

[DEGO]

mind explaining me this ??

well it just have intermediates may be your height  176cm or 167 ,166 170.5  not fixed u r either 170 or 180...
thts the intermediates and sharpcut thing sharpcut is tht no intermediates got it?

[Vin]

Actually i kno wats continuous and discontinuous jus the words "intermediates " and "sharpcut" is new to me ..